CLINICAL STUDIES OF INDUCTION AGENTS XX: A METHOHEXITONE-PROPANIDID MIXTURE

It has previously been observed that with methohexitone and propanidid the incidence and severity of induction side effects increases with increase in dosage. A mixture containing methohexitone 10 mg and propanidid 25 mg per ml was used as main anaesthetic agent with nitrous oxide-oxygen for a standard operative procedure in adult females. It was anticipated that the mixture would be followed by fewer side effects than comparable doses of propanidid and methohexitone alone. This hope was fulfilled and it proved to be a satisfactory induction agent. Dosage studies showed that there was some loss of potency, which is more likely to have affected the propanidid component in view of the pH of the mixture (10.15). It became more acid on storage over six weeks and there was further detectable loss of potency. It is recommended that methohexitone-propanidid mixtures should only be used when freshly prepared.